1. Field of the Invention
The present invention relates to an overhead conveyor for articles to be conveyed suspended from a hanger.
Such overhead conveyors are used, for instance, in clothing factories in order to transport the articles of clothing to storage or delivery points or to transport workpieces to a number of work stations at each of which different operations are carried out on the semi-finished products.
For this purpose, individual delivery points are provided within the overhead conveyor, at which points the hangers which bear the articles of clothing can be moved out of the main conveyor line so as to arrive at a work place located within a side branch or else at the place of storage.
2. Description of Related Art
Federal Republic of Germany OS 17 81 310 discloses an overhead conveyor in which the articles of clothing can be transported by clamps traveling on rollers along a rail.
European Patent OS 0 307 045 (corresponding to U.S. Pat. No. 4,909,373) discloses an overhead conveyor for articles of clothing suspended on hangers in which each clothing hanger is suspended in a respective carrier device. In this carrier device, the articles of clothing are transported within the main conveyance line of the conveyor. Within the conveyor there are delivery points at which the hangers are removed from the main direction of conveyance and delivered into a side branch or a delivery point.
In order to be able to remove the hanger, the suspension device is opened and the hanger drops by its own weight onto a downwardly inclined receiving rod, sliding along it until it has arrived at its destination.
In the design of such an overhead conveyor, it is endeavored to have the removal take place in the direction of the opening in the hanger hook since, in such case, the receiving rod need not be structured to be swingable out of the direction of transport; but rather, hangers which are not to be removed at a removal point can, via the opening in the hanger hook, pass by the rod.
In order to assure the operability of an overhead conveyor having a delivery point arranged in this manner, the hanger hook must be made relatively long so that hangers which are not to be removed, particularly when articles of clothing are suspended from them, can be moved along below the receiving rod while hanging from their hanger hooks, without striking against the receiving rod. As a rule, the hanger hook is too short in, for instance, clothing hangers for carrying trousers, wherein the waist band is clamped between two wire yokes. As a result, the protruding waist band of the trousers comes against the receiving rod instead of passing beneath it, so there is a risk that either the hangers will be rocked so as to interfere with further transport, or that the protruding waist band will be soiled.
Federal Republic of Germany AS 18 04 775 discloses a bipartite removing device for an overhead conveyor, the device being adapted to be swung in the manner of a switch into the conveyor path of the hanger hooks. If the upper part of the switch is swung upward, the hanger hooks transported on the conveyor worm can pass by the delivery point unimpeded. When the upper part is swung downward, the removing device is closed and hanger hooks which are moved up to it are moved away in positive manner from the conveyor worm.
With this device, in order to assure operability, the hanger hook must be made relatively long. Furthermore, the hanger hook is lifted by the upper part of the switch before it is delivered into the other conveyor line. The conveyor path, accordingly, extends obliquely upward for a given distance. The distance in height can be overcome only by the kinetic energy inherent in the hangers, so that a given speed of transport must be maintained for operability.